Reconstruction of the Ocmulgee River, Georgia: 1807-1971

Following European settlement in the late 1700s and early 1800s, the watershed of the Ocmulgee River of Georgia underwent extensive changes in land use. Although the effects of 19th and 20th century changes in land use on stream discharge and the transport of sediments have been well researched, the effect of these variations on stream-channel patterns in the Southern Piedmont and Coastal Plain has not been fully examined. In order to assess historic channel-pattern changes of the Ocmulgee River system, maps of the river channel were prepared from the available data for three time periods—1807, 1903-1910, and 1971. This paper presents the approaches used to reconstruct the Ocmulgee River at these three time periods and to illustrate the application of historical maps in determining fluvial geomorphic change. The 1807 district plats represent some of the earliest documentations of drainage systems in the southeastern United States. Examples of map production quality and tributary mapping, as well as relict riverine features visible on 1941-1969 aerial photography, substantiate the spatial accuracy of the 1807 maps. The evidence indicates that the plat maps are a reliable source of channel-course information and can be used to determine large-scale variations in the position of the Ocmulgee River.